build: Move build related unit test into own job

We shouldn't be asserting on built assets (dist/esm) in our unit tests.

This helps unblock #4616

Author: AbhiPrasad

.github/workflows/build.yml

@@ -411,7 +411,11 @@ jobs:
         with:
           path: ${{ env.CACHED_BUILD_PATHS }}
           key: ${{ env.BUILD_CACHE_KEY }}
-      - name: Run build tests
+      - name: Run browser build tests
         run: |
           cd packages/browser
           yarn test:package
+      - name: Run utils build tests
+        run: |
+          cd packages/utils
+          yarn test:package

packages/utils/package.json

@@ -45,7 +45,8 @@
     "lint:prettier": "prettier --check \"{src,test}/**/*.ts\"",
     "pack": "npm pack",
     "test": "jest",
-    "test:watch": "jest --watch"
+    "test:watch": "jest --watch",
+    "test:package": "node test/package/build.js"
   },
   "volta": {
     "extends": "../../package.json"